Thermoelectric properties of monolayer Sb2Te3

Abstract

The successful demonstration of monolayer films as promising thermoelectric materials highlights alternative strategies to nanostructuring for achieving high thermoelectric efficiency. Due to this reason, the electronic structure and thermoelectric properties of the monolayer Sb2Te3 are studied by using the density functional theory and the semiclassical Boltzmann transport equation. The dynamical stability of the monolayer Sb2Te3 can be guaranteed by the absence of imaginary frequencies in the phonon band structure. The monolayer Sb2Te3 can reduce the lattice thermal conductivity. The Seebeck coefficient S of the p-type monolayer Sb2Te3 is almost three times as high as those of the n-type monolayer Sb2Te3. The power factor for p-type doping is significantly larger than that for the n-type doping. Our calculated ZT values for the monolayer Sb2Te3 are far higher than those of nanomaterials Sb2Te3, bulk Sb2Te3, and the eutectic PbTe-Sb2Te3 composites, indicating that the thermoelectric performance of low-dimensional structure is indeed superior.